Key-operated telephone call transmitter



Jan. 11, 1944. D, R|HARD 2,339,195

KEY-OPERATED TELEPHONE CALL TRANSMITTER Filed May 8, 1941 4 Sheets-Sheet l CWwk A Trap/v5? Jan. 11, 1944. Q Q RlCHARD 2,339,195

KEY-OPERATED TELEPHONE CALL TRANSMITTER Filed May 8, 1941 4 Sheets-Sheet 2 I 6 7 a 9 o 50 4o 74 F! G 4 75' /9 4/ 42 43- /or -44 6; 29 20 3o 32 3/ I Ill 5 2/ 67 r 3r 0' I 5r 24 E v f as 76 O 60 6/ c0 52 /3 I '53 /2 J} 1 54 \l l l /5 A? 55 27 5/ ss sa 64 65 /Nl ENTOR CD. RICHARD A TTORNE V Jan. 11, 1944. c RlCHARD 2,339,195

KHY-(H'I'IRA'IIZI) TIJIJIHHONE CALL TRANSMITTER Filed May 8, 1941 4 Sheets-Sheet 3 VII,"

//v z/g/v r09 C. D. RICHARD ATTORNEY Jan. 11, 1944. Q Q R|HARD 2,339,195

KEY-OPERATED TELEPHONE CALL TRANSMITTER Filed May a, 1941 4 Sheets-Sheet 4 MNO P33 TUV WXY z m F/G-Q o I OPQ;

INVENTOR CZZR/CHARD -W RMW A 7' TORNE V mechanism under the tension Fatented Jan. 11-, 1944 UNITED- STATES LYPA'IIENT OFFICE A knr-or tn l rjg 2321mm: can. I I

Charles D. Richard, alllgnor to Bell West a... Brighton N. Telephone laboratories, In

co'rporated, New York,'N. Y., a corporation of New York Appumhn May s, 1941, Serial No. 392,441 1': Claims. (Cl. 179-90) This'invention relates to telephone call transmitters and more particularly to telephone call transmitters of the key-operated type.

The object of the invention is the provision of a telephone call transmitter of the type above referredto which uses a minimum number of T governor.

operating parts, which is cheap to manufacture.

convenient to operate and positive in operation.

A feature of the invention is the provision of a set of numbered key members for actuating a movable bar a distance corresponding to the movement of the keys from normal to a common stop bar, the movable bar having means normally disposed in operative relation with a gearing mechanism connecting with a pulsing mechanism.

Another feature of the invention is the provision of means actuated by the keys for moving the means carried by the movable bar out of operative relation from the gearing mechanism for permitting the returnmovement of the latter and that of the pulsing mechanism to normal position from different points relative to the being had to being efl'ected under control of a centrifugal speed Another feature is the provision of a mounting oi unit construction punched out of a metallic sheet and formed with bearing portions for the din'erent shafts of the operating mechanism and support elements fora plurality of contact spring pile-ups and for the stop bar used for limiting the movement of the keys. 7

Other novel features and advantages of the invention will appear from the following description and by the claims appended thereto reference the accompanying drawings in which:

Fig. l is a plan view of a telephone desk set fitted with the call transmitter of the invention shown in a slightly reduced scale;

Fig. 2 is a plan assembly view with the casing housing the transmitter mechanism removed from the base. the latter being shown with portions broken away;

Fig. 3 is a right side assembly view, shown 7 with the operating mechanism in normal-nonmovement of the operated key, the return movement of the pulsing mechanism to normal, operating a pulsing contact a number of times corresponding to the value or digit of the operated key.

Another feature is the erable for locking the depressed key in the operated'position while locking the other keys in provision of means on the non-operated position, the operation of the 1 locking means as for releasing the keys being effected at the conclusion of each digit transmitting operation by a bar movable with the gear of a motor spring such tensioning being effected by the operation of the keys.

Another feature is the provision of a mechanism whereby the tensioning of the motorspring is continued. by the operation of the keys following the disengagement of the means carried by the movable bar from the gear mechanism so as to maintain the pressure on the operated key during the operation oi the latter from normal to the stop bar substantially constant. 1 Another feature is the provision of mea whereby the contact actuating means is held out of engageable relation-from the pulsing cam during the rotation of the latter by the manual operation of the keys and released in time relation with each return movement of the pulsing cam to normal-eflected by the tension of the motor spring, the operations of the pulsing mechanism operated position, a number of operating parts being shown in section and with portion broken a a I Fig. 4 is a front assembly view showing the operating parts of the transmitter mechanism in normal non-operated position, the casing and the base being shown in vertical section and with portions broken away:

Fig. 5 is a left side assembly view shown with the operating partsof the transmitter mechanism in normal non-operated position and with a number of operating parts with portion broken away;

Fig. 6 is a view of the mitter mechanism such perspective;

Fig. 7 is a light side assembly view shown with one of the keys and a number of parts actuated thereby in the operated position, parts being shown in section and with portions broken away;

Fig. 8 la a view similar to that of Fig. 7 but showing the operating parts in normal position, a number of parts being shown in section and with portions broken away;' and, v

Fig. 9 is a partial view of the casing housing the transmitter mechanism showing the marking of the keys. I According to the call transmitter of the invention, a mounting i0 shown in Figs. 2, 3, 4, 5 and in detail in Fig. 6, is secured. for example, to the base ll of a telephone desk set by a number of mounting being shown in mounting for the transa number of screws 80 shown in Fig. 5 extending through clearance holes OH in mounting III in engagement with similar screw-threaded holes in the base ll, provision being made in the base if for receiving a casing serving for housing the call transmitter mechanism which will hereinafter be described in detail. 4 Mounting II is formed with upright lug portions l2 provided for supporting a shaft I! on which a set of ten key members Kl, K2, K9, K4, K9, K9, K1, K9, K9 and Kill are pivotally mounted. Key members Kl. K2,K9 etc. are held in normal non-operated position as shown in Figs. 1, 2, 3, 4 and 5 by similar retractile springs l4 having one of their ends hooked to the bridge portion l5 forming the bearing ends of these keys while the other ends of springs l4 are hooked to latching members I! operativeiy associated with the keys, a small distance above the center of supporting shaft l1 on which these latching members are pivoted, shaft I1 being journaled in bearings 19 of mounting i9.

The operation of any one of the key members Kl, K2, K9, etc. from normal position to the position wherein the projections Pl, P2, P9, P4,

P5, P9, P1, P9, P9 and Plll formed with these keys engage a stop bar BX as shown for example by key Kll in Fig. '1 is effective to impart similar angular movement to a common U-shaped bar i9 mounted for free pivotal movement on bearings 2| carried by mounting III. the bar BX being supported at 'both ends to lug members LM formed with mounting i9 and secured thereto as by screws CW.

One of the pivoted arms of bar 19 is formed with a downwardly extending projection 22 best seen in Figs. 8, 5, '1 and 8, to which is pivotally mounted. as on screw wx, a pawl 25 normally en aging under the tension of a spring 14, a pin 29 carried by a sector 21 for actuating the latter in a clockwise direction upon the operation of any one of the key members Kl, K2, K9, etc. Gear sector 21 is keyed on one end of shaft 29 for movement as a unit with an arm 29 keyed to the other end of this shaft. The shaft 29 is supported at both ends in bearings 21 while a bar 24 is secured. as by welding, to projections formed with the gear sector 21 and with the free end of arm 29 in parallel relation to shaft 29 and in engageable relation with projections XY formed with the key latching members [9. The gear sector 21 is limited in its counterclockwise movement as effected by the tension of a motor 29 best seen in Fig. 4 by a stop 29 (see Figs. 3, '1 and 8), formed with the mounting 19, the motor spring 29 being mounted-concentric to shaft 20 with one of its ends hooked to a pin 99 secured to the hub portion of gear sector 21 and its opposite end hooked to a pin 9| secured to the hub of an arm 92 (see Figs. 2, 3, 4, '1 and 8) mounted for free rotation on shaft 29 adjacent the arm 29.

The arm 92 is held from rotation under the normal tension of motor spring 29 by a lever 99 pivoted on a shoulder screw 94 and having at its free end a lug 95 engaging the arm 92, the arm 39 being in turn normally held from pivotal movement by a cam portion 39 formed with the arm of U-shaped bar l9, this lever mechanism serving to yieldably hold the bar 19 in normal position and to perform another function which will be hereinafter described in detail.

The key members Kl, K2, K3, etc. are provided with perpendicularly extending lug portions IY, 2Y, 9Y, 4Y, IY, 91!, 11!, 9Y, 912 and MY best seen in Figs. 2 and 4 disposed in engageable rela- I tion with arms 49, 4|, 42, 49, 44 and 49 keyed or otherwise secured on a shaft 99, joumaled in bearings 99 formed-with mounting l0 as shown in Fig. 6, the arm 49 being actuated by key K9 through lug 9Y, arm 4| by keys KI and K1 through lugs ii! and 1Y; arm 42 by keys K2 and K8 through lugs 2Y and 9Y; arm 49 bykeys K3 and K9 through lugs 3Y and 9Y; arm 44 by keys K4 and Kill through lugs 4Y and IOY and arm 49 by key K5 and through lug 5Y, but it is to be noted that lugs IY, 2Y, 9Y, etc., are disposed at different distances relative to their points of contact with arms 49, 4|, 42, etc. so as to impart a. pivotal movement to shaft 39 at different points relative to the angular movement of the keys Kl, K2, K9, etc., from normal to the stop bar BX and proportional to the rotation of a pulsing cam 59 as will hereinafter be described in detaiL;

The pivotal movement of shaft 99 as effected by the individual operation of key'members Kl, K2, K9 and the arms 40, 4|, 42, etc., is imparted to the pawl 25 against the tension of the spring 14 for disengaging this pawl from pin 29 through a connecting rod 49 having one end pivoted on a shoulder screw 41 carried by pawl 25 and its opposite end pivoted on shoulder screw 49 carried by an arm 49 mounted on shaft 99 for movement as a unit with arms 49, 4|, 42, etc., the arm 49 as shown in Figs. 2, 3, 4 and 8 being formed with a lever member 99 provided for a purpose which will be hereinafter described in detail.

formedintegrally with a spindle 52 having one end journaled in a bearing 59 secured to the upright lug member 54 of mounting 19 and the op.- posite end of this spindle is journaled in a bearing formed with the upright member of mounting II). On the spindle 52,- best seen in Fig. 4, is securely mounted a ten-tooth pulsing cam 59 and on the reduced portion of this spindle is mounted for free rotation thereon a worm gear 51 which is driven, as during the return movement of gear sector 21 to normal under the tension of motor spring 20 through a clutch 59 in the form of a wire winding on the hub portion of cam 59 and on the hub portion of worm gear 51. The operation of worm gear 51 is eflective to actuate the worm W (see Fig. 3) formed with the shaft 59 of a centrifugal speed governor CG provided for controlling the speed of pulsing cam 59 during its operation by the tension of motor spring 29. The governor shaft 59 has one end journaled in a bearing 99 in the right-angle bent portion 9| of upright portion 54 formed with mounting l0 and its opposite end in a bearing, not shown, formed with the drum of governor CG, this drum in turn being secured to a lug 93 formed with the mounting In as by a screw 92.

An inverted U-shaped support 94, best seen in Figs. 2, 3, 4 and 6, straddles the spindle 52 and is secured to the mounting III, as by a number of screws 95. On support 94 is mounted, as on pivot 99, Figs. 3 and 4, a double armed lever member 91, the arm-h of which is provided for engaging the cam 59 and its other arm having a roller 99 of insulating material disposedin operative relation with a contact spring 10 mounted in a pile-up arrangement with a stationary contact spring 11 on a lug LX formed with the mounting Ill. The operation of lever members 91 is effective to cause the make and break operation of the springs 19-" upon the rotation of cam 59 as efrelation from the cam I, this spring being secured at one end to a projection 12 formed with the mounting I. and having its other end resting against a similarly inclined portion of double constant on the depressed key, example key Kil, due to the movement parted to lever It by the cam portion 80 of bar II. and

= the movement imparted by lever 22 to arm 82 to armed lever 61 when the latter is released by the downward movement of arm II as for engaging the pulsing cam 55.

- The spring 1| while holding the pawl 25 normally in engaged relation with pin 26 of gear sector 21, also serves for holding the double arm lever 61 and the arms 4|, ll, 42, etc., in normal position as shown in Fig. 3, this spring having one end hooked to arm 49 mounted on shaft 38 and the other end to a stud projecting from the right disposed upright of mounting It.

The downwardly extending arm 23 keyed on shaft 2| for movement as a unit with gear sector 21 is provided with an insulated stud 15, Figs. 2, .4 and 5, extending in an opening 11 in the left which, as above mentioned, the adjacent end of I the motor spring SI is hooked, in'a'ddition to the tension of retractile spring 14 which acts on the key simultaneously pawlllfrompin 25.

Following a small angular movement of key member Kll from non-operated position and therefore that of gear sector 21, the latching members II are permitted to move in engag'eable relationwith their cooperating latch' elements TS formed with the keys Kl, K2, K2, etc., for

locking the depressed key to the operated position and locking the non-operated keys in their nordisposed upright of mounting II in engageable relation with a spring 12 forming part of a socalled off-normal spring assembly mounted on a supporting lug 1s formed'with the mounting II to perform switching operation well known in the automatic telephone art.

In the operation of the call transmitter of the invention supposing that it is desired to transmit ten pulsesas for calling the operatorlthe op- Z eration of key Kill marked 0 from the position shown in Figs. 2,. 3 and 8 to the operator position shown in Fig. 7, is effective to rotate the spindle 52 through the engagement of pinion 5! with gear sector 21 and thereby the pulsing camv 56 keyed on this spindle one turn in a counterclockwise direction, the movement of gear sector 21 is efiected by the movement of bar 19 and the engagement of pawl 25 with pin 28 carried by gear sector 21.

During the operation of gear sector -21 the arm 50 under the tension of spring 1|, holds the double arm lever 51 in normal position wherein the arm h of this lever is out of engagement with caml. and therefore is not operated. A small distance from the full operated position of key Kll, that is, a small distance prior to the engagement of lug Pll formed withkey Kit to.

stop bar Bx, the pawl 25 is disengaged from the pin 25 through the engagement of lug IIIY, see Figs. 2 and 4,.carried by key Kill with the arm 44 keyed to shaft 38 thus moving the arm 50 in position to cause the engagement-of arm h of lever 81 with the teeth of cam 56 timed to occur simultaneously with the release of gear sector 21 by pawl 25 for permitting the return of the position as effected by the tension of motor spring 29 under control of the speed governor .CG thus actuating the double armed lever 61 and therefore the contact spring 10 once for each tooth of cam 55 for sending ten pulses, the

gear sector 21 being arrested in normal position Upon the disengagement of pawl 25 from the pin 28 on gear sector 21, it is to be noted that the tension of motor spring 2| remains substantially mal positions until released bythe returnrinove ment of gear sector 21 and the consequent engagement of bar 24 with the latching elements It, the release and subsequent return movement of the operated key to normal permitting the reengagement of pawl 25 with pin 28 and the return of arms 4|, 4|, 42, etc., to normal and the transmitter is now ready for a successive operation. Supposing again that it is desired to transmit ilve pulses, the operation of key KI is effective to impart a movement to gear sector 21 for rotating the pulsing cam '58 due to the movement of common bar I! and the engagement of pawl 25 with pin 25 of gear sector 21. The lug-IY,

see Fig. 4, carried by this key is so spaced from its arm as to disengage the pawl 25 from pin 26 following an angular movement of 180 degrees imparted to pinion ll and to pulsing cam such disengagement permitting the return movement of gear sectors and that of cam 58 to normal for actuating the pulsing' contacts 10, 1|, thus transmitting five pulses while the movement of key K5 is continued to the stop bar BX. The make and break operations of the pulsing springs 10-11 are efiected with absolute accuracy notwithstanding considerable plus and minus manufacturing limits in the spacing of thelugs I Y, 2Y 83!, etc., of key members Ki, K2, K3, etc.,

from the arms 40, l I, 42, etc. For example, in'- the operation of key KI under normal conditions of the transmitter mechanism, the pulsing cam 58 is rotated wherein the point PI of this cam is on a line passing from the center of pivot 6 6 and the center of spindle 52 when'the double armed lever member 61 is released by arm 50 and moved under the tension of its retractile spring 12 for 1 positioning its arm h in engageable relation with pulsing cam 58 at the time the pawl 25 is disensaged from pin 25 of gear sector 21, but supposing that after a great number of operations the double armed lever member 01 is released so as to fall at any point on the peripheral rtionof either of the teeth T5 and T5, the release of lever member 61 within this angular movement gear sector and the pulsing cam 58 to normal of cam 56 will not cause the adding or canceling of a pulse since the arm h of lever will begin its operation only by the engagement of tooth'Ti during the reverse movement of the min.

In the operation of the call transmitter of the invention, it has been found that the pulsing op- I erations for the digits 1 to 6 are eflected inless time than that required for the selection and operation of succeeding keys by the operator with the result that the locking mechanisms forthese keys operate only for preventing the manual operation of two keys simultaneously but in" no case delaying the successiv'e operation of; the V higher digit keys beyond the time limit required for the proper operation. of the automatic tensloned by the operation of said key members for returning said cam to normal for actuating said contacts a number of times defined by the operation of said clutch. c

2; A call transmitter comprising a setaf numbered key members, a pulsing cam, a gearing mechanism, normally connected clutch elements actuated in one direction by the operation of said key'members for rotating said cam, means actuated differentially by said key' members for disconnecting said clutch elements for controlling the operation of said cam in said direction, a motor spring tensioned by the operation of said gear mechanism as eiiected by said key members tuating said gear sector upon the operation 01 one or said key members, a mechanism actuated difierentially by said key members for controlling the operation of the first-mentioned mechanism and said pulsing cam, a motor spring for returning said gear sector and said cam to normal following such a control, and a contact actuated by said cam for transmitting a number 01 pulses corresponding to the digit designation of the operated key member. 7 I r v 6. A call transmitter, a set of pivoted key members numbered to represent digits, a stop bar for limiting the angular movement of said pivoted key members, a pivoted bar operated by the movement of each of said key members, a gear sector,

meansnormally operatively connecting said pivoted bar to said gear sector for actuating the latter upon the operation 0! any one of said key members, a pulsing camactuated by the movement of said gear sector, a shait, a pivoted-double armed lever member having one or its arms. for

- operatively engaging said cam, a leversecured to said shaft for holding said two armed lever said shaft, engageddiflerentially by said key for operating said cam in another direction, and

a pulsing contact actuated by the differential operation 01 said cam in the last-mentioned direction. I

3. A call transmitter comprising a set of numbered key members, a bar operated by the operation of said key members, an arm formed with said bar, a gear sector having a pin extending perpendicularly therefrom, a pawl carried by said arm for engaging said pin to cause the operation of saidgear sector upon the ope ration of said key members, a pulsing cam actuated by the movement oi said gear sector, a mechanism actuated by the operation 01' said key members for disengaging said pawlfrom said pin for'controlling the movement of said cam according to the numerical values of said key members, a motor spring tensioned by the operation of said keys members for disconnecting said means from said gear sector for controlling the operation of said cam according to the digit oi. the operated key, a motor spring tensioned by the movement or the operated key for returning said cam to normal following saidcontrol, said lever releasing the double armed lever simultaneously with the i on said shait, means carried by said bar norfor returning said cam to normal, and a contact spring actuated by the operation of said cam.

4. A call transmitter comprising a set of key members, a pivoted bar actuated by the operation of said key. members, a gear sector, a pulsing cam operatively connected to said gear sector, a pawl carried by said bar, normally engaging means carried bysaid gear sector for rotating said cam upon the operation of said her, a stopbar for limiting the movement of said key members, a plurality. of levers, means carried by said key members for engaging said levers for disengaging said pawl from the means carriedby said gear sector for controlling the operation of said cam, a motor spring for returning said sector and said cam to normal, a contact device actuated by the return movement of said cam to normal for transmitting pulses according to the number oi the operated key member and means to cause the reengagement of said .pawl with the means carried by said sector.

5. A call transmitter comprising a set oi. pivoted key members having digit designations, a stop bar for limiting the operation of said key members to similar angular movements, a pivoted bar actuated by said key members an angular distance corresponding to the movement of said key members from normal to said stop bar, a gear sector, a pulsing cam actuated by said gear sector, a mechanism actuated by said pivoted bar for acmally engaging means carried by saidv sector for actuating the latter upon the operation of any one of said key members, a cam rotatable in one direction by the operation of said gear sector, a mechanism actuated by said key members for disen aging the means carried by said bar from the means carried by said gear sector followin the angular motion of said cam corresponding to the numerical values of the operated key members, a motor spring,a lever mechanism actuated by the movement of said bar, said motor spring being mounted concentric to said shaft with one oi its ends secured to one of the levers of said mechanism and its other end to said gear sector to be tensioned by the conjoint operation of the last-mentioned lever and said gear sector during the operation of one of said key members, said gear sector under the tension of said motor spring returning said cam to normal, and a pulsing contact actuated by the return movement or said cam.

8; In a call transmitter a set of keymembers, a mounting having bearings, a U-shaped bar pivoted on the peripheries of said bearings and movable upon the operation of each of said key members,-a stop bar for limiting the movement of said key members, a shaft Journaled in said bearings, a motor spring mounted concentric to said shaft and tensioned by the pivotal movement of said U-shaped bar, a gear sector secured at one end of said shalt, a lever member secured to the opposite end of said shaft, a bar having-one end secured to said gear sector and its opposite end to said lever member, an arm formed with said pivoted bar having means normally engaging said gear sector for actuating the latter upon the operation of any one of said key members, a plurality of latching members one for each of said key members, retractile springs by said key members having one of their ends secured to said keys and their other ends secured to their associated latching members, each of said key members having a toothed lug portion disposed in engageable relation with their associated latching members, said retractile spring causing the engagement of said latching members with said toothed portions for locking the non-operated keys in that position and the depressed key in the operated position upon the movement of said gear sector, said bar disengaging said latching members from said toothed portions upon the return of said gear sector to normal, and a pulsing mechanism actuated by said gear sector upon its return to normal by the tension of said motor p ing.

9. In a call transmitter a set of key members,

a bar extending transverse of said key members,

a gear sector operated in one direction by the operation of said key members acting on said bar, a motor spring tensioned by the operation of said sector in said direction for moving the latter in another direction, a lever mechanism actuated by said key member for defining the extent of angular movement of said gear sector during the continued operation of said bar, a spindle operatively connected to said gear sector, a pulsing cam keyed on said spindle, a contact, means disposed for operation by the movement of said cam. for

actuating said contact, a worm wheel mounted for free rotation on said spindle, a one-way operable clutching device operable upon the operation of said pulsing cam in said other direa tion and a speed governor geared to said worm wheel for controlling the operation of said contact by said cam.

10. In a call transmitter, a pulsing cam, a gearing mechanism for actuating said pulsing cam, a set of digitkey members for actuating said mechanism, and means to render the movement of said key members during their operation variably eitective relative to said mechanism for actuating said cam according to the digit value of said keli members.

11. In a call transmitter, a gearing mechanism, a pulsing element operated by said mechanism, a

set of digit key members for actuating said mechanism, means eilective relative to said key members between normal non-operated positions to stop-operated position ior controlling the operation or said cam to movements proportional to the digits or said key members.

eration of said element by said actuating mechanism.

13. In a call transmitter, a set of key members, a pulsing element, an actuating mechanism for said element, a motor spring for operating said actuating mechanism, a plurality of means actuated by the movement of said key members for operation in opposite direction for tensioning said spring, other means operable by the movement of said key members to render one of said means inefiective relative to said spring for permitting the operation of said actuating element y the tension of said spring, the other of said first-mentioned means continuing the tensioning of said motor spring during the movement of said key members to full-operated position.

14. In a call transmitter, a contact, a set of digit key members, a rotatable pulsing cam, a bar extending transverse of said key members for operation by the movement thereof, means for controlling the operation of said key members in their movement from normal non-operated to full-operated position, and a mechanism actuated by said bar for imparting movement to said cam for actuating said contact according to th value of the depressed key.

15. A call transmitter comprising a pulsing contact, a set of key members, a common bar extending transverse of said key members for operation therewith, a gearing mechanism actuated differentially by the movement of said key members, a cam actuated by said gearing mechanism, and -means for returning said key members to normal non-operated position independently of the return movement of said cam for operatin said contact. a

16. A call transmitter comprising a pulsing contact, a set of key members, a motor spring-tensioned by the operation of each of said key members, a gear sector responsive to the tension of said spring, a pulsing cam actuated by the movement of said gear sector, latching means operable upon the movement of said gear sector as eifected by said key members for blocking the depressed key in the operated position against the tension of said spring during the operation of said gear sector for actuating said contact.

17. A call transmitter comprising. -a pulsing contact, a set of key members, a motor springtensioned by the operation of each of said key members, a Bear sector actuated in one direction by the movement of each of said key members, a lever member, a cam actuated by the movement of said gear sector for actuating said lever member, means normally in position to render the operation of said cam during the manual operation or said key members ineffective relative to said lever member, said means operating upon the return of said gear sector by the tension'of said spring to render the movement of 12. In a call transmitter, a pulsing element, an f sautumn eflective relative to said lever member actuating mechanism for said element, a Jetn digit key members variably efiectively movable between normal non-operated positions to fullior actuating said contact, a latching mechanism operable upon the movement or said gear sector, by any one or said key members for blocking operated position, means actuated by Sam key the depressed key to operated position and the members for imparting movements to said mechanism Ior actuating said element inefiectively according to the effective operation 01 said key membars, a motor spring for eflectively actuating said element, other means actuated by said key membars 101' continuing tensioning said motor spring il ldwmembmindependentlyoitheopnon-operated keys to normal non-operated'position, and means operable upon the operation of said cam in direction eflective relative to said lever member for controlling the operation 0! said contact, the return oi'said gear sector to normal non-operated position releasing all the key members.

CHARLES D. RICHARD. 

